F^-离子对Li_2O-Al_2O_3-SiO_2系微晶玻璃晶化的影响  

Effect of Fluorine on the Crystallization of Li_2O-Al_2O_3-SiO_2 Glasses

作　　者：胡安民[1] 梁开明[1] 顾守仁[1] 

机构地区：[1]清华大学材料科学与工程系,北京100084

出　　处：《无机材料学报》2003年第6期1163-1168,共6页Journal of Inorganic Materials

摘　　要：采用差热分析(DTA),X射线衍射分析(XRD),扫描电镜(SEM等分析手段研究了F-离子对Li_2O-Al_2O_3-SiO_2系微晶玻璃形核和晶化的影响.结果发现,引入F-离子使得玻璃的析晶峰值温度降低,玻璃的析晶活化能E降低,晶化指数n加大.引入F-离子后,一方面促进了玻璃析晶和晶化,Li_xAl_xSi_(1-x)O_2固溶体析出以及Li_xAl_xSi_(1-x)O_2固溶体向β-锂辉石固溶体转变加快,晶化后的晶粒尺寸加大,析晶活化能E,晶化指数n与扫描电镜(SEM)分析一致.表明F-离子促进了玻璃晶化和离子扩散.The nucleation and crystallization behavior of Li2O-Al2O3-SiO2 glasses with varied amounts of Fluorine content were investigated by the differential thermal analysis (DTA), X-ray diffraction, (XRD) and the scanning electron microscopy (SEM). The results show that with the increase of the fluorine concentration, the crystallization peak temperature (T-p.) decreases, the crystallization I activation energy (E) decreases, the Avrami exponent (n) increases.. The onset of the precipitation of LixAlxSi1-x O-2 crystal and its transformation to beta-spodumene all shift to lower temperature and the grain size increases with the fluorine added. The values of the Avrami exponent (n) and the crystallization activation energy (E) agree well with the scanning electron microscopy observation of equivalent axis grain crystal. The results suggest that the fluorine promotes the initial crystallization and ion diffusion in the glass system.

关 键 词：差热分析 Li20-Al2O3-SiO2系微晶玻璃 形核 晶化 

分 类 号：TQ171[化学工程—玻璃工业]